Plant comprising pressure medium generators working in parallel



y 21, 1940- J. E. JOHANSSQN 2,201,683

rum COMPRISING Panssuaz MEDIUM eammnoaswonxme m PARALLEL Fil ed June 19,19:57 s SheetS-Shee't 2 /A6 we r0 FUEL 1mm 7/0 VALVE Maya, 1940- J. E,JOHANSSON PLANT COMPRISING PRESSURE MEDIUM GENERATORS WORKING INPARALLEL Filed June 19, 1937 I5 Sheets-Sheet 3 I) an j load on theplantvaries.

Patented May 21, 1940 PLANT COMPRISING PRESSURE MEDIUM GENERATORSWORKING IN PARALLEL Johan Erik Johansson, Goteborg, swedenpassignor toAktiebolaget Gotaverken, Goteborg, Sweden, a corporation of SwedenApplication June is, 1937, Serial No. 149,08

In Sweden November 9, 1985 4 Claims. (01. sir- 91) This inventionrelates to plants comprising two or more pressure-medium generators,which comprise pumps driven by internal combustion engines, and in'whichthe delivery portions of different generators communicate with eachother and the pressure medium is used for driving one or morereciprocating or rotating motors or supplied to other pressure mediumconsumers. The generators in such plants may comprise internalcombustion engines driving liquid or elastic fluid pumps and thepressure medium produced by said generators maybe compressed air orother gas, a mixture of compressed air and superatmosphericv combustiongases from the internal combustion engines, steam, pressure liquid orthe like.

In plants of this type it may be desired for difierent purposes to keepconstant, for instance, the numbers of revolutions of the internalcombustion engines or the pressure in a common pressure conduit orreceptacle, to which the generators supply pressure medium, or tocontrol the outputs of the generators in such a manner that allgenerators are operated on a predetermined portion ofv the total outputof the plant or so that, for instance, one or more generators operate onconstant output, whereas variations of load on theplant are taken careof by other generators, whose outputs stand in a certain relation toeach other, or so that the numbers of revolutions oi the internalcombustion engines or the pressure of the medium produced by thegenerators are varied in a desired manner, when the The invention may,for instance, be employed in. plants producing compressed air andcomprising two or more compressors working in parallel and driven byinternal combustion engines, and adapted to feed a common pressureconduit or receptacle, and in which it may, for instance, be desired toprevent the load from being unequally divided between the differentinternal combustion engines so that one engine is overloaded or speeds.In such plants it is also often required that the pressure in thepressure'conduit or the receptacle fed by the generators be keptconstant, or that the variations in pressure be kept withincertain'flxed limits. The invention may also be employed in other powerplants, for instance in the propelling plants of vessels or inmobileplants, such as railroad engines or the like,- in which driving gasgenerators comprising internal combustion engines and air compressorsdriven thereby and working in parallel are employed for the productionof a superatmospheric driving gas mixture for driving main engines andsometimes also auxiliary engines. In a marine plant two or more drivinggas generators may be adapted to feed one or more propelling engines andsometimes also auxiliary engines of difierent kinds. The auxiliaryengines are usually operated at fixed numbers of revolutions,- and thepropelling engine or engines at more or less varying numbers ofrevolutions and'load. In such plants some engines, for instance one ormore propelling engines, may be operated on a driving gas mixture of acertain high pressure, whereas the auxiliary engines, and, for instance,one or more propelling engines may be operated on a driving gas mixtureof a different pressure.

The invention may also be employed in pump plants comprising pumpsdriven by internal combustion engines and delivering pressure media ofthe same or different pressures for one or more purposes, for instancein pump plants for water works, fluid pressure plants providing adriving medium for cranes and other machinery, etc.

The present invention, which takes full consideration of the abovementioned conditions, substantially consists in the provision of fuelsupply controlling means for the internal combustion engines consistingof a member common for two or more controlled internal combustionengines and parts cooperating therewith, said member and parts beingmovable relatively to one another, and said member or parts beingdirectly or indirectly influenced by the numbers of revolutions 01' saidcontrolled internal combustion engines and con nected with fuel supplydevices of the diflerent internal combustion engines in such a mannerthat upon a displacement of the member orvone or more of the partscaused by a change in the number of revolutions of the internalcombustion engines, which stand in a predetermined relation to eachother, such achange of the fuel supply to said internal combustionengines is achieved that the predetermined relation between said numbersof revolutions is restored.

Other features of novelty will be hereinafter disclosed in connectionwith the description of one embodiment of the invention illustrated inthe accompanying drawings, in which:

Fig. 1 is a perspective view of the controlling device of a plantcomprising two driving gas generators provided with a hydrauliccontrolling device, 1

Fig.- 2 is a diagrammatic view on a larger scale and partly in sectionor a part of the hydraulic controlling device employed in the plantillustrated in Fig. 1;

Fig. 3 is a cross-section, on the line III-III of Fig. 2, of one of thehydraulic motors used in the controlling device illustrated in Figs. 1.and 2;

Fig. 4 is a cross-section on the line IVIV of Fig. 2; and

Fig. 5 is a longitudinal section of one of the driving gas generatorsdiagrammatically illustrated in Fig. 1 and of a propelling engine drivenby the gas produced by the generators as indicated diagrammatically inFig. 1.

Fig. 1 is a diagrammatic view of a plant, in which pressure mediumgenerators comprising pumps driven by internal combustion engines areincluded and in which said generators produce a pressure medium andsupply the same to a conduit common for two or more generators and thegenerators are provided with fuel supply controlling means, which willbe more particularly described hereinbelow.

The plant illustrated in Fig. 1 comprises two driving gas generators I36and I31, which may, for instance, each comprise two Diesel cylinders I38and a compressor cylinder I38 built together therewith and communicatingtherewith through conduits I40. A typical construction of suchapparatus, which per se may be varied in design within the scope of thepresent invention, is shown more fully in Fig. 5. Each driving gasgenerator supplies a driving gas mixture to a conduit I4I or otherreceptacle common for both. generators, said driving gas mixture beingcomprised by the combustion gases of the internal combustion engines I38and compressed air from the compressors I39, which may be mixed with thecombustion gases of the internal combustion engines somewhere after saidengines or may pass totally or'partially through the internal combustioncylinders. The driving gas mixture is supplied to the top and bottom ofthe cylinders of a double-acting three-cylinder reciprocating engine I42through a manifold I43, and the engine I42 may be connected to thepropeller shaft of a vessel or any other stationary or mobile machinery.

Fuel is supplied to the internal combustion cylinders I38 through fuelinjection valves I44, I45 and fuel supply controlling devices I46, I41,which may be of any suitable type and, for instance, constructed in amanner similar to the fuel pumps illustrated in Figs. 4 and 10 of mycopending application Serial No. 186,090. Fig. 2 in the accompanyingdrawings illustrates such a fuel supply control device in section on alarge scale, and furthermore, this figure and Figs. 3 and 4 illustratein detail the hydraulic controlling device of the generator I36 and apart of the controlling device of the generator I31 cooperatingtherewith. In the embodiment of the invention illustrated in Figs. 1 to5 a gear pump I48, I48, respectively, is connected to each driving gasgenerator and driven by the respective generator, said gear pump beingadapted to draw a liquid such as oil from a receptacle I through pipesI5I and I52, respectively, and to pump said oil through pipes I53, I54,I55, I56 and I51, I58, I59

' and I60, respectively, to hydraulic motors I6I and I82, which in thepresent case are illustrated as gear motors. From the gear motors I6Iand I62 the oil flows back through pipes I63 and I64, respectively, tothe receptacle I50. In Fig. 2 the gear motor I6I is illustrated in sideelevation and the gear motor I62 in vertical section. The gear motorsare connected to each other by means of a shaft so arranged as to causethe motors to rorate together, but to permit a certain angulardisplacement between the motors. The gear motors IM and I82 are arrangedin such a manner that if one motor tends to increase its number ofrevolutions relatively to the other a by-pass I66 or I61, respectively,is opened in the gear motor, whose number of revolutions is increasing.The oil pressure at the pressure side of said gear motor is then reduceddue to the reduced resistance to the oil flow from the respective gearpump to the receptacle I50 in the respective gear motor, and as a resulttherefrom the fuel supply to the corresponding driving gas generator isreduced. For this purpose pipes I68 and I68 are connected to the pipesI53, I54 and I51, I58, respectively, said pipes I68, I68 formingcommunications between the pressure side of the gear pumps I48, I46 andcylinders I10, I1I, respectively, in which spring-actuated pistons I12,I13 are movable. The pistons I12 and I13 are connected to regulatingsectors I14, I15, respectively, by means of connecting rods I16, I11,respectively, said sectors being connected to the fuel supply controldevices I46, I41, respectively, by means of links I18, I18,respectively, or the like. Manual adjustment of the fuel supply isobtained by means of levers I80, I8I, which may be locked in differentpositions relatively to the sectors I14, I15 by means of suitablelocking devices as illustrated in detail in Fig. 2. The fuel supplycontrol device I46 is illustrated in section in Fig. 2. The link I18 isconnected to a lever 1I secured on the shaft 15, which has an eccentric11 for each cylinder of the internal combustion engine secured thereon.The eccentric 11 actuates one end of a lever 18 bearing with a roller 16on a cam 85 provided on a shaft 86 driven in any suitable manner fromthe internal combustion engine I36 and making one revolution each time afuel injection is desired in the cylinder corresponding to the cam 85.Fuel is supplied to the fuel pump through a pipe 80 and is admitted fromthe chamber 8I through an opening controlled by a valve 82 to thepressure chamber 83. A plunger 84 is pressed into the chamber 83 againstthe action of a spring by means of the cam 85 on the shaft 86. A springloaded valve 88 is provided in the wall between the pressure chamber 83and the chamber 8|. An abutment such as an adjusting screw 88 or thelike on the lever 18 is adapted to press the valve 88 in certainpositions of the cam 85 and the eccentric 11 and thereby to cause thevalve 88 to open and the pressure in the chamber 83 and the fuelinjection to cease. The opening of the valve 88 occurs during thepressure stroke of the pump plunger 84 and interrupts'the high injectionpressure produced by said plunger at an earlier or later stage of theplunger stroke so that a smaller or larger fuel quantity is injected inthe internal combustion cylinder, according to the momentary positionstaken by the levers H and 18. Thus the fuel supply is reduced orincreased according to the positions taken by the piston I12 and thesetting of the arm I80 relatively to the sector I14. Cylinders I82, I83are inserted in the pressure pipes I55, I56 and I58, I80, respectively,the outlet openings of said cylinders, which communicate with the pipesI56, I being controlled by pistons I84, I85, respectively, displaceablymounted in said cylinders and connected to springs I88, I81 actuated bymeans of a device I 88 acting through levers I88, I 80 and rods I8I andI82 connected to said springs. The pressure in the cylinders I 82, I 83may be adjusted at willube means of the pressure controlling de- Figs.2, 3, and 4 show in detail an embodiment of the gear motors I6I and I62.In this embodiment said motors comprise casings having gear wheels I95,I96 and I91, I99, respectively, mounted therein. Each motor casing isprovided with an inlet opening I99 and an outlet opening 200, asillustrated in Fig. 3. The gear wheels I95 and I91 are each providedwith a radial duct 20I and 202, respectively, openingin the bottom of atooth gap of the respective gear wheel. The gear wheels I95, I91 arerotatably mounted on a common shaft I provided at each end with a bore206 and 205', respectively, with which the by-pass pipes I66 and I61,respectively, are connected. Said bores may, in a certain angularposition of the gear wheels relatively to the common-shaft I65, bebrought into communication with the ducts 20I and 202. through openings206 and 201, respectively. The shaft I65 is provided with two arms206and 209 having sleeves M0 and 2I I, respectively, pivotallymountedtherein. Each hub of the gear wheels I95, I91 is elongated, asillustrated in Figs. 2 and 4, and forms an arm 2I2 and 2I3,respectively. Sleeves 2I6 and 2 I5 are pivotally mounted in said arms,the open ends of said sleeves being slidably mounted on the sleeves 2I0,2, respectively. Helical springs 2I6, 2I1 are provided within thesleeves 2I0, 2I6 and '2II, 2I5, as illustrated in detail in Fig. 4, andconnected with their ends to the sleeves.

In this manner an elastic coupling between the gear wheels I95 and I91is obtained, which permits a certain angular displacement of the gearwheels relatively to each other, whereas said gear wheels aresimultaneously caused to follow each others movements.

Obviously, if one gear motor tends to increase its number of revolutionsrelatively to the other, a moment is transmitted from one gear motor tothe other through the shaftI65. The duct 20I or 202, respectively of thegear wheel I96 or I91, which tends to increase its number ofrevolutions, is then turned in such a manner that the inner opening ofsaid duct opens a communication to the opening 206 or 201, respectivelyin the shaft I65. Thus a by-pass through the pipes I66 or I61,respectively is opened at the gear'motor, which tends to increase itsnumber of revolutions, since the oil from the pressure sideof the motorgets .a more or less unobstructed passage through the respective duct20! or 202, opening 206 or 201, and bore 206 or 205, substantially whilethe tooth gap communicating. with the duct passes through the outletchamber of the respective gear motor. Consequently, the pressure fallsin the oil pipes at the pressure side of said gear motor causing the oilpressure in the cylinder I10 or "I, respectively, communicating with therespe'ctive pressure pipe to fall and the piston moving .in saidcylinder to move downwards, see Figs. 1 and 2, underthe influence of thespring, and to reduce the fuel supply'to the respective internalcombustion engine.

The controlling means illustrated in Figs. 1 to 5 operate in thefollowingmanner:

If, for instance, the pressure controlling device I96 is adjusted insuch a manner that the spring pressures on the two pistons I66 and 195are the same, the'pressures prevailing in the cylinders 162 and I93 willbe equal, if the piston areas are of the same size. The levers I 60 andI9I, which are manually adjusted for a certain desired output of thedriving gas'generators, may, for instance, be adiusted in,such'positions that the same fuel quantities are supplied to the' driving gasgenerator I36 and to the driving gas generator I91. If the generatorsare equal and supply a driving gas mixture to the common conduit.-

It is further assumed that the pistons I12, I12 then take the positionsindicated in Fig. 1. It is then obvious that, as long as the load on thedriving gas generators is not changed,.the pressures in the pressurepipes I56, I60 remains constant, the gear motors I6I, I62 run at exactlythe same numbers of revolutions, and no moment is transmitted by theshaft I65 between'the gear motors. The arms 206, 209 and the arms 212,2I3 formed by the; hub portions of the gear wheels I95, I91 are thenrotating together with the gear wheels, and the gear wheels take thepositions'reiatively to each other and to the shaft I65 illustrated inFigs. 2, 3, and 4.

Now, if, for instance, by some reason the number of revolutions of thedriving gas generator I36 falls, the number of revolutions of the gearpump I69 is also reduced correspondingly. The oil quantity delivered bythe pump I66 is then also reduced and the number of revolutions of thegear motor I6I consequently tends to decrease. Then the gear motor I62transmits a twisting moment to the motor I6 I through the shaft I65resulting in a certain angular displacement of the shaft I65 relativelyto the gear wheels I95 and I91. Said angular displacement iscontinuously increased, whereas the pressure in the pipe-system I53,I56, I55, which is dependent upon the spring pressure on the piston I66.remains substantially constant, and the piston I96 is displaced somewhatdownwards and throt ties the oil flow to the pipe I56. Due to theangular displacement between the gear wheel 0 I91 and the shaft I65 theinner end of the duct 202 is gradually moved towards the opening 201until communication is obtained between the outlet side of the gearmotor I62 and the bore 205. Obviously, the opening 206 simultaneouslymoves awayfrom the duct 20I and the springs 2I6 and 2" are compressed.Then the oil can pass the gear motor I62 with reduced resistance, andflow through the by-pass I61 to the outlet side of said gear motor.Consequently, the pres-" sure inthe cylinder I1I falls and the piston.I19 moves downwards, see Fig. 1, so that the fuel supply to thegenerator I31 and the number of revolutions of said generator arereduced. This reduction continues as long as there is a tendency ofdifference in the number of revolutions between the driving gasgenerators I96 and I31.

If now, for instance, the number of revolutions of the driving gasgenerator I96 by some reason increases, the oil quantity pressed throughthe pipe system I53, I56, I55, I56 rises. The piston I96 is then pressedupwards and an increased oil quantity is supplied to the gear motor III.

Consequently, the number of revolutions of said motor increases, and amoment is transmitted to the gear motor I62. A relative angulardisplaceand a reduction of the number of revolutions of said generator,until both generators are again running at the same speed.

If the total output of the plant is desired to be changed the oilpressure controlling device I88 is manually adjusted so that the tensionof the springs I88, I81 acting upon the pistons I84 and I85,respectively, is increased or reduced. This adjustment may naturallyalso be made automatically. If the tension of the springs is increased,i. e. if the operating lever of the pressure controlling device I88 ismoved to the left in Fig. 1, the oil pressures in the pipes I53, I54,I55 and I51, I58, I59 are increased. Then, the oil pressures in thecylinders I10 and HI are also increased, and the pistons I12 and I13 arepressed upwards and both driving gas generators I38 and I31 are suppliedwith greater fuel quantitles. The driving gas generators are thenrunning at a mutually equal but higher number of revolutions than that,at which they were running on the prior adjustment of the lever I88.Correspondingly, the fuel supply to the driving gas generators and theoil pressures in the pressure pipes of the pumps I48 and I49,respectively, and the chambers connected thereto are reduced, if theoperating lever of the 'pressure controlling device I88 is moved to theright in Fig. 1, so that the spring pressure on the pistons I84 and I85-is reduced.

Obviously controlling means of the type des'cribed in connection withFigs. 1-5 may be used whether the plant comprises driving gas generatorsproducing a super-atmospheric driving gas mixture or a number ofcompressors or pumps drivenby internal combustion engines and supplyinga gaseous or liquid pressure medium to a conduit or other space commonfor two or more pressure medium generators. The plant illustrated inFig. 1 may naturally also comprise more than two engines working inparallel. In the plant described in connection with Figs. 1-5 theinternal combustion engines working in parallel comprised in the plantare continuously driven at the load, for which the plant is adjusted,since. upon a change of the operating conditions of one engine. thecontrolling means influenced by the engines operating in parallelactuates the supply of fuel to the controlled internal combustionengines so that the equal distribution between the different engines isrestored. In all plants according to the invention the total fuel supplyto the generators may be dependent upon the pressure or quantity of themedium produced by the enerators or the numbers of revolutions of one ormore of said generators and adjusted through automatically or manuallyoperated means.

If more than two generators are driven in parallel a gear motor of thetype indicated in Figs. 1-5 may be associated with each generator in thesame way, as illustrated in Fig. 1, and the gear motors of allgenerators comprised in such a plant may be coupled by a transmission ofthe type indicated in Figs. 1-5. Where -gear motors are used it isobvious that several ducts 2! and 282 may be provided in the gear wheelsof the motors, and also several openings 206, 201, respectively.

If, for instance, in the plant according to Fig. 1, it is desired todrive one generator with constant output, the fuel controlling device ofsaid generator may be locked by means such as a swingable pawl 81, Fig.2, which is somewhat offset relative to the arm I88 in order not tointerfere therewith, and which may engage the sector I14, as indicatedin dotted lines in Fig. 2. The piston I12 or I13, respectively, maythen, if desired, be disengaged from the sector I14 or I15,respectively, in any suitable manner. A valve 90 provided in the pipeI68 or I89, respectively. may serve the same purpose as the pawl 81. Ifthe back pressure of the driving gas generators or other pressure mediumgenerators is desired to be kept constant such control may be caused byshutting off the by-pass by means of a valve 9| at the gear motor, whosecorresponding generator is desired to run on constant output.

What I claim is:

1. In a plant, the combination of pressure medium generators comprisingpumps driven by internal combustion engines, a communication betweendelivery portions of said generators, a control device for regulatingthe speed of at least two of said internal combustion engines tomaintain the operation thereof in desired speed relation with respect toeach other, a shaft in said control device common for said controlledinternal combustion engines, a liquid pump coupled to each one of thecontrolled internal combustion engines, a liquid motor corresponding toeach one of said liquid pumps and elastically connected to said shaftand communicating with and driven by the pertaining liquid pump, fuelsupply control devices for each one of the controlled internalcombustion engines responsive to the pressure in the communicationbetween the pertaining liquid pump and the liquid motor, means adaptedto influence the pressure in said communications upon a certain angulardisplacement of one of said liquid motors relatively to said shaft, sothat said pressure which actuates the fuel supply control device of thepertaining internal combustion engine is changed corresponding to saidangular displacement, whereby to tend to bring the speeds of thecontrolled engines to said desired speed relation.

2. In a plant, the combination of pressure medium generators comprisingpumps driven by internal combustion engines, a communication betweendelivery portions of said generators, a control device for regulatingthe speed of two or more of said internal combustion engines to maintainthe operation thereof in desired speed relation with respect to eachother, a shaft in said control device common for said controlledinternal combustion engines, a liquid pump coupled to each one of thecontrolled internal combustion engines, a liquid motor,comprising a gearpump working as a motor corresponding to each one of said liquid pumpsand communicating with and driven by the pertaining liquid pump, a gearwheel in each liquid motor provided with a duct and rotatably mounted onand connected to said common shaft by means of an elastic coupling,openings in said shaft corresponding to the ducts in said gear wheelsand adapted to open a by-pass at the respective gear motors upon turningof the gear wheel a certain angle relatively to the shaft, and a fuelsupply control device for each generator responsive to the pressure inthe communication between the pertaining liquid pump and liquid motorand adapted to reduce the fuel supply to the generator upon opening ofsaid by-pass.

3. In a plant, the combination of pressure medium generators comprisingpum driven by internal combustion engines, a communication betweendelivery portions of said generators, a control device for regulatingthe speed of at least two of said-internal combustion engines tomaintain the operation thereof in desired speed relation with respect toeach other, a rotatable member in said control device common for saidcontrolled internal combustion engines, a liquid pump coupled to eachone of the controlled internal combustion engines, a liquid motor foreach controlled internal combustion engine displaceably connected withsaid rotatable member and driven by the pertaining liquid pump,communications between said liquid pumps. and the pertaining liquidmotors, fuel supply control devices for each one of the controlledinternal combustion engines responsive. to the pressure of the liquid inthe communication between the pertaining liquid pump and the pertainingliquid motor, and means in said liquid motors adapted to influence thepressure in said pertaining communication upon displacement of thepertaining liquid motor relatively to the rotatable member, whereby totend to bring the speeds of the controlled engines to said desired speedrelation.

4. In a plant, the combination of pressure medium generators comprisingpumps driven by internal combustion engines, a communication betweendelivery portions of said generators, a control device for regulatingthe speed of at least two 01' said internal combustion engines tomaintain the operation thereof in desired speed relation with respect toeach other, a rotatable memher in said control device common for saidcontrolled internal combustion engines, a liquid pump coupled to eachone of the controlled internal combustion engines, a liquid motor foreach controlled internal combustion engine displaceably connected withsaid rotatable member and driven by the pertaining liquid pump, acommunication between each liquid pump and the pertaining liquid motor,fuel supply control devices ior each one of the controlledinternal-combustion engines responsive to the pressure of the .liquid inthe communication'between the pertaining liquid pump and the pertainingliquid motor, means in said liquid motors adapted to influence thepressure in said pertaining communication I upon displacement of thepertaining liquid motor relatively to the rotatable member to therebyadjust the fuel supply control device of'the pertaining internalcombustion engine so as to .tend to restore said desired speed relation,and auxiliary J CHAN ERIK J OHANBSON.

